1. Technical Field
The present invention relates to a device for moving headrest back and forth for automobile, and more particularly, to a device for moving headrest back and forth for automobile by which the automobile headrest can be moved back and forth or returned to its original position by pushing it backward.
2. Background Art
Automobile headrests are generally mounted on top of a backrest of a car seat and designed to pivot on a shaft by means of a tilting device. The headrest is used as a head support, while it may be lifted, lowered or tilted for the occupant's convenience. The headrest can also perform the function of supporting the back of the occupant's head to protect the occupant's neck from being injured in the event of a rear-ended car accident.
Recently, known are tiltable automobile headrests with a monitor attached thereto for TV programs or visual traffic information on the screen being watched by the passenger on the rear seat.
Examples include a device for moving headrest back and forth of the U.S. Pat. No. 6,000,760 of the present inventor, disclosure of which is incorporated by reference. As shown in FIGS. 1 to 3b, the device comprises a stay 10 with a horizontal portion 11 and a pair of parallel vertical portions 12 extending from both ends of the horizontal portion 11; a ratchet member 20 fixed to the horizontal portion 11 of the stay 10 and having a plurality of teeth 21 and a jaw 22, a tilt adjusting device 30 having a pair of parallel side panels each having a lower portion in pivotal engagement with the horizontal portion 11 of the stay 10; a first torsion coil spring 40 mounted on the horizontal portion 11 of the stay 10; a check member 50 having teeth 51 and a jaw to prevent the reverse rotation of the tilt adjusting device 30; and a second torsion coil spring 60, opposite ends of which are respectively hung on upper parts of one of the side panels 31 of the tilt adjusting device 30 and the check member 50; a back and forth movement device 100 provided with two pairs of levers 90 and arranged to move a cover 80 back and forth; and a mobile shaft 95 connecting the device 100 to the tilt adjusting device 30.
In the above described device for moving headrest back and forth, the cover 80 is moved back and forth by means of two pairs of front and rear levers 90. When the headrest is to be returned to the original front position from the intermediate or rear position, the cover 80 is pushed back further and thus the headrest itself is moved to the utmost rear position.
After the teeth 51 of the check member 50 engage fully with the teeth 21 of the ratchet member 20, the teeth 51 is then disengaged from the teeth 21 by means of a pushing force applied to the cover 80 and the force of the second torsion coil spring 60 so that the headrest carried by the traversing device 100 may be returned to the original position by the force of the first torsion coil spring 40, when the pushing force is removed.
However, the above described traversing device has problems in that it has a relatively complicated structure, as the tilt adjusting device and the back and forth movement device are separately required, resulting in increased production costs and time and lowered work efficiency during manufacture thereof.